1. Field of the Invention
The present invention relates generally to burners and in particular to a dual cannister gas housing for the combustion of two separate gases having different heating values.
2. Description of the Prior Art
Gases of relatively low heating value are becoming increasingly available. For example, commercial supplies of anaerobic digestion gas, sanitary landfill gas and coke oven gas are now available and the utilization of such gases is highly desirable in times of increasing energy costs. Because such gases have a lower heating value per unit of volume than more conventional fuels, such as natural gas, a higher quantity thereof is typically required to satisfy the heat input requirements of conventional burner equipment. To realize the commercial value of such gases, one of two approaches may be used. First, gas pressure can be increased. This approach is usually limited by the pressure from the supply source of the low heating value gas. In many instances, there simply is insufficient pressure to supply the volume of gas required. Second, the pressure can be maintained at a low level and the burner housing orifices can be increased in area. This approach is also limited by the fact that once orifice size is increased sufficiently to utilize the lower heating value gas, if it is desired to revert back to the higher heating value gas, the entry velocity and pressure drop thereof will be inadequate for proper combustion.
It would be highly desirable to have the capability of burning such low heating value gases in a system which also burns higher heating value gases, such as natural gas. At the same time, it would be highly desirable to be able to regulate gas flow velocity and pressures to insure proper combustion of the gas mixture.